将json jar添加到classpath java中

Question

我是Java世界的新手.我想添加Json lib来编译我的程序.我从这里下载了文件.

当我尝试编译程序时

  javac -classpath json.jar MyClassName.java

我收到错误:

Note: JsonSimpleExample.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

当我试图跑:

java MyClassName

我越来越:

Exception in thread "main" java.lang.NoClassDefFoundError: org/json/simple/JSONObject
    at MyClassName.main(MyClassName.java:9)
Caused by: java.lang.ClassNotFoundException: org.json.simple.JSONObject
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
    ... 1 more

我在哪里弄错了？

Answer 1

你必须使用-classpath何时运行java.

java -classpath json.jar MyClassName